Compact disk reader

ABSTRACT

A compact-disk player for playing a compact disk that carries data in a plurality of program blocks recorded on the disk. The program blocks are dividable into sections by indices which are stored for each program block. Each index has starting and ending times that are also stored. Any index within any program block may be selected, and an optical scanner scans the compact disk to be played. The amount to be skipped by the optical scanner to arrive at a position that corresponds to the selected index, is calculated from the stored starting and ending times.

The present application is a continuation of the parent application Ser.No. 328,078 filed Feb. 9, 1989 now abandoned.

BACKGROUND OF THE INVENTION

The invention concerns a compact-disk reader wherein the first index forthe individual program blocks recorded on a compact disk is stored.

The article Zusammenstellen eines CD-Programms ("Compiling a CDProgram"), pages 26-28, Funkschau 15 (Jul. 18, 1986) describes what dataare recorded on a compact disk and how a compact-disk reader processesthem.

Each compact disk has a table of contents of data that provideinformation about the number of program blocks recorded on the disk,their starting times, and the overall playing time of the disk. Theindividual program blocks are as a rule musical selections, althoughthey can also represented spoken texts or soundtracks for films andslideshows. Although up to 99 program blocks can be recorded on onecompact disk, disks of music usually contain nor more than 10 to 20different selections.

The table of contents of a compact disk has the data format illustratedin FIG. 1. The first block, A0, contains the title of the first musicalselection, the second block, A1, that of the last selection, and thethird block, A2, the overall playing time. The following blocks, Dl-Dn,contain the starting times of the n individual selections recorded onthe disk. Blocks A0. A1, A2, and D1-Dn are combined into a group, inwhich the table of contents of the disk is completely stored.

Since the total amount of memory available on the disk for the table ofcontents is in the lead-in track and is completely occupied by severalof these directly adjacent groups, the data relating to the table ofcontents of the disk are stored multiply redundantly.

When the disk is played, the starting points Dl-Dn, which comprise mostof the data stored in the table of contents when there are more thanthree selections, are employed to calculate the starting times of theindividual selections.

As illustrated in FIG. 2, the disk's lead-in track ES is followed by apause PE with a prescribed duration of two to three seconds. Pause PE isfollowed by the individual program blocks, the four selections B1, B2,B3, and B4 illustrated in FIG. 2 for example. The last program block,selection B4, is followed by a lead-out track AS. The individual programblocks can be separated by pauses of durations that are notstandardized. Between the first program block B1 and the second programblock B2 in FIG. 2 is a pause P1, and between second program block B2and third program block B3 is a pause P2, whereas fourth program blockB4 follows third program block B3 directly. Pause P1 can be longer forexample than pause P2.

Each program block is identified with a number to differentiate it fromthe others. The number tells the compact-disk reader what program blockits pick-up is scanning at any moment. Furthermore, each program blockhas at least one and no more than 99 indices that can be employed todivide the block into up to 99 sections of any length. The indices forone program block extend from 01 to 99 and from 00 to 99 when there is apause between two blocks. The index 00 is always assigned to a pause.

In FIG. 2 for example first program block B1 has only one index, 01,second program block B2 is divided into three sections by indices 01,02, and 03 and third program block B3 into two sections by indices 01and 02, and fourth program block B4 also has only one index, 01.

The total disk-playing time from the end of lead-in track ES to the endof lead-out track AS is stored parallel. The playing time of theindividual program block is similarly stored inside each block, startingwith time t=0. Stored parallel with each pause between two programblocks is the length of the pause, beginning, however, with the lengthof the pause at the start of the pause and ending at the end of thepause with the value zero. At this point the time is counted backwardsas with a countdown, and the following four items of information areaccordingly available to the compact-disk reader at the very instant itsbeam of light is scanning a location within a program block:

the playing time elapsed between the end of lead-in track ES and thelocation in question,

the time elapsed between the beginning of the program block and thelocation in question,

the number of the program block, and

the index assigned to the location in question.

If the scanning beam strikes a pause between two program blocks, thefollowing three items of information are available:

the index 00, indicating a pause,

the playing time elapsed between the end of lead-in track ES and theparticular location in the pause, and

how long the pause still has to go or, in other words, after how manyseconds the next program block will begin.

The potential for dividing a program block into up to 99 indices aspecial advantage for longer musical selections or literary works. Thecompact-disk manufacturer can for example use the indices to specify thesolos--piano solos or solos by a particular singer, arias, duets, orchoruses in an opera. In works of literature they can indicatemonologues or dialogues by particular persons for example.

SUMMARY OF THE INVENTION

The object of the present invention is to design a compact-disk readerthat will allow the indices to be processed.

This object is attained in accordance with the invention in that theindices for the individual program blocks recorded on a compact disk canbe stored along with their starting and ending times in a memory.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the table of contents of a compact disk;

FIG. 2 is a schematic view of an arrangement of program blocks andindices;

FIG. 3 is a schematic view and shows the essential elements, accordingto the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention will now be described with reference to one embodiment byway of example.

A compact disk CD is inserted and its table of contents conventionallyread. The disk is then incrementally scanned by scanner AV in order tostore in storage SP the indices of the individual program blocks,individual musical selections for example, along with their associatedstarting and ending times. It is accordingly possible for the listenerto select by selection unit T and listen in sequence to particularpassages in a selection, solos by a particular singer for example,assuming that the passages are characterized by indices on the disk.

One advantage of the invention is that the extent to which the reader'soptical pick-up will skip forward to arrive at a particular selection orpassage within a selection can be calculated by calculator ST from thestarting and ending times of the indices, as is possible with the datastored in the table of contents, because the table lacks precisely thosestarting and ending times, as it does the lengths of the individualpauses between the selections. When, on the other hand, the lengths ofthe pauses are known in that they have, as in accordance with theinvention, been calculated from the starting and ending times of theindices, the access times for desired selections will be decreased.Furthermore, the remaining playing time for a selection or programmedsequence that is being played at any moment can be displayed moreprecisely. The remaining playing time and the overall playing time of acurrently playing index can also be displayed.

In another embodiment of the invention the indices and their associatedstarting and ending times are automatically stored in a memory while thecompact disk is being played. Of particular advantage is a combinationof the first and second embodiments that allows the listener either tostore the indices and their starting and ending times first or to beginlistening immediately.

In a fourth embodiment of the invention the ending time of lead-in trackES is stored. This measure decreases the access times because the lengthof lead-in track ES is not standardized and because no time zero must beassigned to its beginning. The lead-in track can for example start attime 12 seconds and end at time 50 seconds, the stored ending time.

In a fifth embodiment of the invention the indices and starting andending times of several compact disks can be stored and characterizeddisk-by-disk in a memory.

It is of particular advantage for this purpose to provide a residentmemory so that the stored indices, their starting and ending times, andthe lead-in track ending time will not be erased when the reader isturned off, but will be immediately available when it is turned onagain.

I claim:
 1. A compact-disk player for playing a compact disk carryingdata in a plurality of program blocks recorded on said disk, saidprogram blocks being dividable into sections by indices, comprising:storage means for storing all indices of each program block, each ofsaid indices having starting and ending times; said storage means alsostoring said starting and ending times; means for selecting any indexwithin any program block; an optical scanner for scanning a compact-diskto be played; and means for calculating an amount to be skipped by saidoptical scanner dependent on the index selected and from stored startingand ending times of selected indices upon selecting a desired indexwithin a desired program block, storing said indices and calculatingsaid amount to be skipped by said optical scanner providingsubstantially rapid and precise skipping from one program block toanother selected program block with predetermined index.
 2. Acompact-disk player as defined in claim 1, wherein said compact disk hasa lead-in track with an ending time, said ending time of said lead-intrack being stored also in said storage means.
 3. A compact-disk playeras defined in claim 1, wherein indices of individual program blocks aswell as respective starting and ending times are stored in said storagemeans after insertion of a compact disk in said player.
 4. Acompact-disk player as defined in claim 1, wherein indices of individualprogram blocks and respective starting and ending times are stored insaid storage means while a compact disk is being played.
 5. Acompact-disk player as defined in claim 1, wherein indices withrespective starting and ending times of a plurality of compact disks arestored in said storage means together with identification for eachcompact disk.
 6. A compact disk player as defined in claim 1, whereinindices with respective starting and ending times are stored in saidstorage means and remain stored in said storage means after switchingoff said compact-disk player.
 7. A compact-disk player for playing acompact disk carrying data in a plurality of program blocks recorded onsaid disk, said program blocks being dividable into sections by indices,comprising: storage means for storing all indices of each program block,each of said indices having starting and ending times; said storagemeans also storing said starting and ending times; means for selectingany index within any program block; an optical scanner for scanning acompact-disk to be played; and means for calculating an amount to beskipped by said optical scanner dependent on the index selected and fromstored starting and ending times of selected indices upon selecting adesired index within a desired program block; said compact disk having alead-in track with an ending time, said ending time of said lead-intrack being stored in said storage means after insertion of a compactdisk; indices of individual program blocks together with respectivestarting and ending times being stored in said storage means afterinsertion of a compact disk; said storage means retaining said indicesand respective starting and ending times after switching off saidcompact-disk player, storing said indices and calculating said amount tobe skipped by said optical scanner providing substantially rapid andprecise skipping from one program block to another selected programblock with predetermined index.